<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>函数自我调用</title>
</head>
<body>
<p>函数可以自动调用：</p>
<p id="demo"></p>
<script>
    (function () {
        document.getElementById("demo").innerHTML = "Hello!我是自己调用的";
    })();
</script>
</body>
</html>